1. Field of the Invention
This invention relates to a bearing holder used for holding a bearing into a through hole of a gear case or a bearing fixed part of a yoke of a motor equipped with a reduction gear, for example.
2. Description of the Prior Art
There have been various structures of such bearing holders in the past. Among them, there has been a bearing holder having a structure as shown in FIG. 5 and FIG. 6.
The bearing holder 101 is formed with an elastic material, and has a structure comprising a fitting face 106 secured to an inner peripheral face 105 of a bearing fixed part 104 provide at an end of a through hole 103 of a gear case 102 and plural bearing stoppers 108 contacting a spherical oilless bearing 107 along its outer periphery, as shown in FIG. 5 and FIG. 6.
After the bearing holder 101 is inserted into the bearing fixed part 104, the outer periphery of bearing fixed part 104 is punched at several points. Deformation caused by the punching of the fitting face 106 of the bearing holder 101 acts as a stopper for the bearing holder 101 by itself, and the oilless bearing 107 is held in the gear case 102 even if an armature shaft 109 supported by the oilless bearing 107 is off-centered owing to the elasticity of the bearing holder 101.
However, in the aforementioned conventional bearing holder 101, there is a problem in that there are too many steps required for punching the periphery of the bearing fixed part 104 of the gear case 12 in order to make a stop of the bearing holder 101.
Additionally, there is another problem in that the oiless bearing 107 sometimes can not be supported securely when the armature shaft 109 is off-centered because deformation of the fitting face 106 of the bearing holder 101 is sometimes not enough to act as a stopper by itself.
There is a further problem in that the bearing stopper 108 is deformed causing the oilless bearing 107 to be dislodged if the motor receives an impact.